For more than a decade it has featured on the world's maps. Viewed from Google Earth, Sandy Island appears as a dark, tantalising sliver, set amid the shimmering vastness of the Pacific Ocean.
But when marine scientists arrived at the island in the Coral Sea off Australia they were in for something of a shock: it didn't exist. Where there was supposed to be a sandy outcrop complete with palm trees, a few coconuts and maybe a turtle there was merely blue undulating water.
The Australian scientists, led by Maria Seaton, a geologist at Sydney University, had embarked on a voyage to study plate tectonics. They noticed that the enigmatic island lay along their route.
But there were several puzzling discrepancies: though the island appeared on the Google Earth map, there were no images of it.
It had also featured for the past 12 years on the usually reliable world coastline database. But there was no sign of it on their sea chart.
Dr Steven Micklethwaite, a crew member from the University of Western Australia, recalled: "We went upstairs to the bridge and found that the navigation charts the ship uses didn't have it.
"And so at that point we thought: Well, who do we trust? Do we trust Google Earth or do we trust the navigation charts?"
The scientist added: "This was one of those intriguing questions. It wasn't far outside of our path. We decided to actually sail through the island … Lo and behold, there was nothing! The ocean floor didn't ever get shallower than 1 300 metres below the wave-base. There's an island in the middle of nowhere that doesn't actually exist."
Micklethwaite told the Sydney Morning Herald that the ship's captain was nervous about running aground and proceeded cautiously as they made their "un-discovery".
"We all had a good giggle at Google as we sailed through the island. It was one of those happy circumstances in science. You come across something somebody has never noticed before."
The scientists would now send the correct data to the authorities to get the world map fixed, he said.
A perfect map
The non-discovery took place during a 25-day expedition by Australia's Marine National Facility, on board its RV Southern Surveyor research vessel.
Had the island existed it would have belonged to France, because its location near the archipelago of New Caledonia is in French territorial waters.
Danny Dorling, president of the British Society of Cartographers, said it was not surprising that the error had crept in. "You can't create a perfect map. You never will," he said. "Our current world map is a collection of highly accurate satellite maps and some of the oldest data collected from Admiralty charts."
Dorling said that in the case of Sandy Island it was probably human error that had led to its creation.
The cartographer said it was just possible that Sandy Island –now a non-island, according to its Wikipedia entry – would have the last laugh.
"It's unlikely someone made this island up. It's more likely that they found one and put it in the wrong location. I wouldn't be surprised if the island does actually exist, somewhere nearby." – © Guardian News & Media 2012